Feasibility of utilizing the B-10/n,alpha/Li-7 reaction in investigating MOS integrated circuit structures

Difficulties in carrying out microautoradiographical studies of boron in silicon are discussed, and an approach to determining the depth of boron penetration in a MOS gate oxide layer is developed (using alpha-emitting Li produced by neutron bombardment of the boron). The feasibility of using particle track detectors to discern the extent of boron impurity diffusion and distribution in silicon oxide and in monocrystalline silicon is probed. Irradiation, etching, and microautoradiography techniques are indicated briefly. Successfully microautoradiographed specimens clearly showing source and drain channels are displayed.